General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DES-24-0177
Thesis topic details
Category
Earth and environmental science
Thesis topics
Transverse dispersion of pollutants in a river with riffle-pool systems : example of the middle Durance River
Contract
Thèse
Job description
When releasing a pollutant into a river, it is important to know the downstream distance from which the pollutant will be homogeneously distributed throughout the cross-section, in order to be able to delimit the mixing zone. To estimate this, the usual method is to apply an advection-diffusion model based on the estimation of a transverse mixing coefficient. While numerous formulas exist for estimating this coefficient, most of them have only been validated in certain river configurations.
In a previous study, Lorris Gond [2022] divided a part of the Durance into successive reaches, according to the hydromorphological facies encountered, and determined the transverse mixing coefficient in each section by releasing dye. These results confirm the hypothesis of a transverse mixing process specific to the riffle-pool sequences encountered in the Middle Durance. The aim of the proposed thesis is to verify this hypothesis in rivers with riffle-pool type structures. The aim is then to determine a methodology for computing a global mixing coefficient for the structure based on a priori knowledge of the facies, so as to avoid the need for new in situ measurements each time the bed undergoes morphogenic changes. To this end, the thesis will involve field characterization of the geometry of a section of the middle Durance, dye release to quantify the transverse mixing coefficient in the river, and laboratory experiments on a small-scale riffle-pool structure.
A master internship is proposed by the team in addition to the thesis.
University / doctoral school
Mécanique, Energétique, Génie civil, Acoustique (MEGA)
INSA Lyon
Thesis topic location
Site
Cadarache
Requester
Position start date
01/10/2024
Person to be contacted by the applicant
KATEB Lylia lylia.kateb@cea.fr
CEA
DEN/DTN/SMTM/LMTE
CEA CADARACHE
0442253394
Tutor / Responsible thesis director
BERNI Céline celine.berni@inrae.fr
INRAE
RIVERLY
5 rue de la Doua 69100 Villeurbanne
04 72 20 10 77
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